Flowing liquid laser

Abstract

Abstract Stimulated emission of radiation (laser action) is produced in materials generally classed as dyes. These dyes may be dissolved in a liquid solution. A quantity of dye in a flowing liquid solution in a module is pumped or excited by a laser beam radiating in the ultraviolet region which is focused to a line with a cylindrical lens. A rectangular beam of such radiation is produced by a pulsed cross field nitrogen gas laser. The focused line which is transverse to the beam produced by the exciting laser, and transverse to the direction of the flowing dye lies near the surface of the dye material in the working region of the module, and is substantially as long as the cell is wide. The module being an integral unit with a cell, reservoir, and circulating means attached, the working region of which lies within an intensifying optical cavity which may be formed by a 100% reflecting mirror and a 10% mirror both perpendicular to the line of focus of the pumping radiation. The stimulated emission from the dye material is characterized by a short pulse width and little loss of energy between the two lasers. High pulse rates with dye circulation, and high conversion efficiencies of the dye when so pumped, are obtained. For frequency adjustment the optical cavity substitutes for the 100% mirror a grating or Littrow prism at the appropriate angle. Further spectral narrowing is obtained by inserting a tilted Fabry-Perot etalon in the cavity. By using such a frequency tuner and a plurality of dye materials which emit stimulated radiation over different portions of the spectrum, the present device can provide laser radiation for virtually the whole visible spectrum and into the infrared and ultraviolet.

Inventors

• 👤 R Caristi

Bibliographic Details